Glock 21 SF

by FRANK BORELLIEquipment Reviewer On Aug 10, 2007

Borelli Consulting

The Glock 21 SF

Photo credit: Frank Borelli

The Glock 21

Photo credit: Glock

For a long time now, there has been some speculation as to what the Glock Model 40 would be. I've been dreaming about a single-stack .45ACP with an 8+1 capacity and a 4.5 to 5-inch barrel. I've been told that although such a weapon is on the "wish list," it's not likely to be the next weapon made. To be honest, I never expected Glock to make another gun in .45ACP after they came out with the G37, G38 and G39 in .45GAP. I was quite surprised to see the Glock 21SF being released and have to wonder if it doesn't represent the potential fourth generation of Glock evolution. Let's take a look at what's different and whether that difference is good or bad.

Shown here to the right, the Glock 21SF has some minor exterior design changes as compared to the Glock 21 (shown below right). The Glock 21, a standard third generation Glock pistol, sports the molded-in finger grooves in the grip frame and a mounting rail on the dust cover for mounting lights or lasers. The Glock 21SF incorporates three changes, two of which I fully understand and appreciate, and the third which I may not appreciate a lot, but that does make sense.

The first change from Glock 21 to Glock 21SF is the ambidextrous magazine release. While I'm not a design or mechanical engineer, I never really thought that this would be a hard thing to do. Glock did it, though, without making it a lever that's pulled down to achieve magazine release. To top it off, Glock also had to redesign their magazines to address the differences in the original G21 and the G21SF. Their new magazines will function in both designs, but the old magazines don't have the necessary cut out in the front of the magazines to function in the new weapon. The magazine capacity didn't change: you still get 13 rounds of .45ACP in the mag, plus one more in your chamber.

The second design modification is the size of the grip frame. When I first handled a G21SF, I didn't immediately notice a difference, but when I had the chance to handle a G21 next to a G21SF side by side, the difference became obvious. This is definitely something you need to feel to appreciate. That 13 rounds of .45ACP fit into so comfortable a grip and one so slim is amazing to me. Part of the difference in size is easily observed when you look at the grip frame from the bottom. The dead space behind the magazine well is much smaller on the G21SF than it is on the G21. That isn't the only change, though there is also a noticeable difference in the thickness of the grip frame on either side of the mag well. If I'd had a set of calipers to measure the difference with, I'd report on exactly what it is. Unfortunately, I just have to say, "It felt thinner and was more comfortable in my hand."

The third design modification is the inclusion of a full MIL-SPEC 1913 Picatinny rail system on the dust cover. If you compare the photo at right to that of the standard G21 below it, the difference in the rail mounting system is easy to see. I'm sure there is a benefit to this design modification, but in my working world there was no need for it.

Between the three design mods, I find the slimmer grip to be the most valuable. The ambidextrous magazine release has a high utilitarian value as well. The Picatinny rail on the dust cover is better to have and not need than need and not have. So, how does it all add up on the range?

My test G21SF fed and fired all of the different types of ammo I put through it without a hiccup. The assortment of ammo I fired included:

general junk reloads that I bought at a local gun show some years ago;

some old CCI Lawman 230g JHPs;

Federal Hydra-Shok JHPs

Speer Gold Dot JHPs

Winchester 230g FMJ (ball)

UMC 230g FMJ (ball)

For all that, I experienced zero failure-to-feed malfunctions. Every round fed with no issues. Prior to starting my time at the range, I had lubed the G21SF as follows: I took a cotton swab with a drop of MiliTec-1 on it, and ran the swab the inside of the rails on the slide. Nothing else was lubed or treated. At no point did I ever notice the slide moving back into battery slow due to carbon or powder residue.

I also didn't experience any malfunctions as misfires. Every round chambered fired with a single strike. Ejection was positive and, thanks to the sharp recoil of the .45ACP cartridge, the brass was cleared fast and well. I found some ejected brass as far as twenty feet away. Reloads were quick and easy as the magazines fell free of the mag-well with a good push on either side of the ambi-mag release.

I wasn't shooting to test fine accuracy, but throughout my afternoon of shooting, I had no issues keeping all rounds inside the 8-ring (rapid fire) and the 9-ring (slow fire) on a standard B27 target. On a TQ-15 target I was able to easily keep everything inside the smaller of the two boxes. Recoil was more than manageable and was even referred to as "comfortable" by a female student shooter on the range that afternoon.

As a long-standing fan of both Glocks and the .45ACP round, I've found myself thinking longer and harder about the G21SF. Again, while the Picatinny rail on the dust cover doesn't matter to me, I appreciate the versatility of the ambidextrous magazine release and the increased shooting comfort had from the slimmer grip profile. If you haven't had opportunity to handle one of these weapons, seek the experience out. Take my advice though: don't shoot one unless you have the money to spend adding it to your collection.